In a suspended ceiling system having main runner members and cross members arranged in a grid pattern to support ceiling panels, the present invention is directed to a staked-on connector or clip, which is attached to the ends of the cross members to be inserted through a slot in the main runner and to form a connection between the cross member and the main runner.
A staked-on connector of this type is disclosed in U.S. Pat. No. 4,989,387, whose disclosure is incorporated herein by reference thereto. This staked-on connector has a U-shaped tab bent out of one surface adjacent a distal end with an aperture forming a portion of the U-shaped tab also forming a first abutment surface, a second abutment surface being deformed out of the connector on a second surface adjacent the proximal end and a third abutment surface for engaging the web of the main runner lying on a line extending substantially midway between the first and second abutment surfaces. When this connector is inserted through a slot in a web of a main runner, the tab will engage an opposite surface of the web of the main runner and the first and second abutment surfaces will be approximately at equal distances on each side of the web of the main runner as the third abutment surface engages the web. The staked-on connector also has two spacing bumps which extend out of the first surface to engage an edge of the slot to urge the two staked-on connectors of two runners extending into the slot from opposite directions toward each other. Other staked-on connectors are disclosed in U.S. Pat. Nos. 4,108,563; 4,161,856; 4,611,453; and 4,779,394.
When utilizing a staked-on connector in a suspended ceiling system which is fire-rated, such as a system similar to that disclosed in U.S. Pat. No. 4,601,153, the third abutment surface is supposed to pierce the web of the main runner to relieve expansion forces. The connector element requires substantial rigidity to prevent buckling and/or bending. While this rigidity can be obtained in the connector disclosed in U.S. Pat. No. 4,989,387, by utilizing a thicker material for forming the staked-on connector, problems can sometimes occur.